Wasps to Be Introduced to Save Trees

Using insects to fight insects, officials are scheduled today to release tiny Australian wasps at Valley Village Park in the San Fernando Valley to attack the red gum lerp psyllids that are plaguing eucalyptus trees.

It will be the first use of the wasps to combat the psyllids in the United States, said Gilda Franklin, spokeswoman for the Los Angeles City Department of Recreation and Parks, which is coordinating the effort.

Researchers have been studying the wasps since August to ensure that their introduction will not pose environmental hazards, she said.

The insects do not sting people or harm beneficial psyllids, which are tiny flying bugs that suck sap from foliage.

UC Berkeley professor Donald Dahlsten, the leading researcher on the problem, will release 100 male and 100 female wasps, each about the size of a comma, at the park.

With a name thousands of times bigger than the insect--Psyllaephagus bliteus--the tiny wasps have been bred through several generations while in quarantine at the university’s College of Natural Resources Center for Biological Control.

The lerp psyllids, which also originated in Australia, where eucalyptus trees are native, were discovered in El Monte in 1998 and are now widespread throughout the state. The infestation at Valley Village Park, one of the worst in the city, was brought to the attention of city officials a year ago after a resident, Patricia O’Connell, contacted The Times.

The bugs have since stripped trees of foliage in many areas, including Chandler Boulevard, where some of the trees appear dead.

“All of the trees are suffering and are very sick looking,” said O’Connell, who takes daily walks through her neighborhood and the park. “I am afraid we are going to lose them.”

Dahlsten and his research assistants were en route to Los Angeles on Tuesday and could not be reached for comment.